HIV-1 reservoirs continue to exist in latent form despite long-term suppression of circulating virus with antiretroviral therapy. The main challenge in achieving a cure for HIV-1 infection is the persistence of these latent viral reservoirs. Assays that allow for identification, characterization, and isolation of latently infected single cells fo downstream genomic sequencing are needed to efficiently and fully characterize HIV-1 reservoirs. However, existing assays that analyze latently-infected cells require burdensome and costly serial cell dilutions. Other proposed methods to identify and analyze HIV-infected cells require significant investment in costly equipment and reagents and have not been adapted for downstream characterization of latent reservoirs. We propose to develop and validate an innovative and novel assay using microfluidic methods with PCR for identification, enumeration, and isolation and downstream characterization of viral genomes from latently-infected human cells. The application of our approach will be particular useful in the analysis of samples from patients on combination antiretroviral therapy and/or in studies of novel modalities of reservoir eradication. Specific aims include: 1) develop and test the efficacy of the proposed method to identify and enumerate latently-infected human PBMCs, tissue derived macrophages, and other primary human cells using microfluidic methods and PCR, and, 2) validate our assay to isolate single-cell droplets with integrated HIV-1 DNA for downstream sequencing and secondary target gene quantification. This two-year development grant will utilize innovative approaches and adaptations of existing microfluidic technologies to develop an assay to characterize HIV- reservoirs on the single-cell level in patients on antiretroviral therapy. Our proposal involves principal investigators with different but complimentary research backgrounds and experiences, including translational virology and bioengineering/biophysics. Our prior experiences in the detection and quantification of very low-levels of HIV-1 genetic material and in the development of microfluidic devices for viral and immune characterization will be crucial to the development of novel assays to identify and characterize HIV-infection at the single-cell level. The proposed method has the potential to be adapted for a wide variety of multidisciplinary research studies, such as single-cell characterization of viral and intracellular pathogens or analysis of stem cells and/or malignant tissues.